Risk factors for acute kidney injury after Stanford type A aortic dissection repair surgery: a systematic review and meta-analysis

Background: Risk factors for acute kidney injury (AKI) after Stanford type A aortic dissection (TAAD) repair are inconsistent in different studies. This meta-analysis systematically analyzed the risk factors so as to early identify the therapeutic targets for preventing AKI.Methods: Studies exploring risk factors for AKI after TAAD repair were searched from four databases from inception to June 2022. The synthesized incidence and risk factors of AKI and its impact on mortality were calculated.Results: Twenty studies comprising 8223 patients were included. The synthesized incidence of postoperative AKI was 50.7%. Risk factors for AKI included cardiopulmonary bypass (CPB) time >180 min [odds ratio (OR), 4.89, 95% confidence interval (CI), 2.06–11.61, I² = 0%], prolonged operative time (>7 h) (OR, 2.73, 95% CI, 1.95–3.82, I² = 0), advanced age (per 10 years) (OR, 1.34, 95% CI, 1.21–1.49, I² = 0], increased packed red blood cells (pRBCs) transfusion perioperatively (OR, 1.09, 95% CI, 1.07–1.11, I² = 42%), elevated body mass index (per 5 kg/m²) (OR, 1.23, 95% CI, 1.18–1.28, I² = 42%) and preoperative kidney injury (OR, 3.61, 95% CI, 2.48–5.28, I² = 45%). All results were meta-analyzed using fixed-effects model finally (p < 0.01). The in-hospital or 30-day mortality was higher in patients with postoperative AKI than in that without AKI [risk ratio (RR), 3.12, 95% CI, 2.54–3.85, p < 0.01].Conclusions: AKI after TAAD repair increased the in-hospital or 30-day mortality. Reducing CPB time and pRBCs transfusion, especially in elderly or heavier weight patients, or patients with preoperative kidney injury were important to prevent AKI after TAAD repair surgery.     

Risk factors of acute kidney injury in patients with Stanford type B aortic dissection involving the renal artery who underwent thoracic endovascular aortic repair

BackgroundAcute kidney injury (AKI) is one of the most common and serious complications in patients with type B aortic dissection (TBAD). This study aimed at investigating the incidence and risk factors of in-hospital AKI in TBAD patients involving the renal artery who underwent thoracic endovascular aortic repair (TEVAR) only.MethodsA total of 256 patients who were diagnosed as TBAD combined with renal artery involvement were included in this retrospective study. All patients were divided into the AKI group and the non-AKI group according to the KDIGO criteria. The risk factors for AKI were identified using a multivariate logistic regression model.ResultsA total of 256 patients were included in this study, and the incidence of AKI was 18% (46/256). Patients in the AKI group were more likely to have a higher proportion of the youth, a higher level of body mass index, and a shorter time from onset to admission. Multivariate logistic regression analysis revealed that the youth (age ≤40 years) (OR: 2.853, 95%CI: 1.061–7.668, p = .038) were prone to AKI, and lower estimated glomerular filtration rate (eGFR) (OR: 1.526, per 15-ml/min/1.73 m² decrease, 95%CI: 1.114–2.092; p = .009), higher diastolic blood pressure (DBP) (OR: 1.418, per 10-mmHg increase; 95%CI: 1.070–1.879; p = .015), and fasting blood glucose (FBG) ≥7 mmol/L on admission (OR: 2.592; 95%CI: 1.299–5.174; p = .007) were independent risk factors for AKI.ConclusionsHigher incidence of AKI had been perceived in this study, most of them were young and middle-aged patients. Renopreventive measures should be considered in those high-risk patients with younger age, lower eGFR, higher DBP, and higher FBG on admission.     

Coronavirus-associated kidney outcomes in COVID-19, SARS,and MERS: a meta-analysis and systematic review

ObjectivesA meta-analysis and systematic review was conducted on kidney-related outcomes of three recent pandemics: SARS, MERS, and COVID-19, which were associated with potentially fatal acute respiratory distress syndrome (ARDS).MethodsA search of all published studies until 16 June 2020 was performed. The incidence/prevalence and mortality risk of acute and chronic renal events were evaluated, virus prevalence, and mortality in preexisting hemodialysis patients was investigated.ResultsA total of 58 eligible studies involving 13452 hospitalized patients with three types of coronavirus infection were included. The reported incidence of new-onset acute kidney injury (AKI) was 12.5% (95% CI: 7.6%–18.3%). AKI significantly increased the mortality risk (OR = 5.75, 95% CI 3.75–8.77, p < 0.00001) in patients with coronavirus infection. The overall rate of urgent-start kidney replacement therapy (urgent-start KRT) use was 8.9% (95% CI: 5.0%–13.8%) and those who received urgent-start KRT had a higher risk of mortality (OR = 3.43, 95% CI 2.02–5.85, p < 0.00001). Patients with known chronic kidney disease (CKD) had a higher mortality than those without CKD (OR = 1.97, 95% CI 1.56–2.49, p < 0.00001). The incidence of coronavirus infection was 7.7% (95% CI: 4.9%–11.1%) in prevalent hemodialysis patients with an overall mortality rate of 26.2% (95% CI: 20.6%–32.6%).ConclusionsPrimary kidney involvement is common with coronavirus infection and is associated with significantly increased mortality. The recognition of AKI, CKD, and urgent-start KRT as major risk factors for mortality in coronavirus-infected patients are important steps in reducing future mortality and long-term morbidity in hospitalized patients with coronavirus infection.     

The effects of acute kidney injury in a multicenter cohort of high-risk surgical patients

Background and objectivesPatients who develop post-operative acute kidney injury (AKI) have a poor prognosis, especially when undergoing high-risk surgery. Therefore, the objective of this study was to evaluate the outcome of patients with AKI acquired after non-cardiac surgery and the possible risk factors for this complication.MethodsA multicenter, prospective cohort study with patients admitted to intensive care units (ICUs) after non-cardiac surgery was conducted to assess whether they developed AKI. The patients who developed AKI were then compared to non-AKI patients.ResultsA total of 29 ICUs participated, of which 904 high-risk surgical patients were involved in the study. The occurrence of AKI in the post-operative period was 15.8%, and the mortality rate of post-operative AKI patients at 28 days was 27.6%. AKI was strongly associated with 28-day mortality (OR = 2.91; 95% CI 1.51–5.62; p = 0.001), and a higher length of ICU and hospital stay (p < 0.001). Independent factors for the risk of developing AKI were pre-operative anemia (OR = 7.01; 95% CI 1.69–29.07), elective surgery (OR = 0.45; 95% CI 0.21–0.97), SAPS 3 (OR = 1.04; 95% CI 1.02–1.06), post-operative vasopressor use (OR = 2.47; 95% CI 1.34–4.55), post-operative infection (OR = 8.82; 95% CI 2.43–32.05) and the need for reoperation (OR= 7.15; 95% CI 2.58–19.79).ConclusionAKI was associated with the risk of death in surgical patients and those with anemia before surgery, who had a higher SAPS 3, needed a post-operative vasopressor, or had a post-operative infection or needed reoperation were more likely to develop AKI post-operatively.     

Outcomes of critically ill patients with acute kidney injury in COVID-19 infection: an observational study

BackgroundEarly reports indicate that AKI is common during COVID-19 infection. Different mortality rates of AKI due to SARS-CoV-2 have been reported, based on the degree of organic dysfunction and varying from public to private hospitals. However, there is a lack of data about AKI among critically ill patients with COVID-19.MethodsWe conducted a multicenter cohort study of 424 critically ill adults with severe acute respiratory syndrome (SARS) and AKI, both associated with SARS-CoV-2, admitted to six public ICUs in Brazil. We used multivariable logistic regression to identify risk factors for AKI severity and in-hospital mortality.ResultsThe average age was 66.42 ± 13.79 years, 90.3% were on mechanical ventilation (MV), 76.6% were at KDIGO stage 3, and 79% underwent hemodialysis. The overall mortality was 90.1%. We found a higher frequency of dialysis (82.7% versus 45.2%), MV (95% versus 47.6%), vasopressors (81.2% versus 35.7%) (p < 0.001) and severe AKI (79.3% versus 52.4%; p = 0.002) in nonsurvivors. MV, vasopressors, dialysis, sepsis-associated AKI, and death (p < 0.001) were more frequent in KDIGO 3. Logistic regression for death demonstrated an association with MV (OR = 8.44; CI 3.43–20.74) and vasopressors (OR = 2.93; CI 1.28–6.71; p < 0.001). Severe AKI and dialysis need were not independent risk factors for death. MV (OR = 2.60; CI 1.23–5.45) and vasopressors (OR = 1.95; CI 1.12–3.99) were also independent risk factors for KDIGO 3 (p < 0.001).ConclusionCritically ill patients with SARS and AKI due to COVID-19 had high mortality in this cohort. Mortality was largely determined by the need for mechanical ventilation and vasopressors rather than AKI severity.     

Retrospective analysis on incidence and risk factors of early onset acute kidney injury after lung transplantation and its association with mortality

ObjectivesAcute kidney injury (AKI) is a common complication after lung transplantation (LTx) which is closely related to the poor prognosis of patients. We aimed to explore potential risk factors and outcomes associated with early post-operative AKI after LTx.MethodsA retrospective study was conducted in 136 patients who underwent LTx at our institution from 2017 to 2019. AKI was defined according to the Kidney Disease: Improving Global Outcomes (KDIGO) guideline. Univariate and multivariate analyses were conducted to identify risk factors related to AKI. The primary outcome was the incidence of AKI after LTx. Secondary outcomes were associations between AKI and short-term clinical outcomes and mortality.ResultsOf the 136 patients analyzed, 110 developed AKI (80.9%). AKI was associated with higher baseline eGFR (odds ratio (OR) 1.01 (95% confidence interval (CI): 1.00–1.03)) and median tacrolimus (TAC) concentration (OR 1.15 (95% CI: 1.02–1.30)). Patients with AKI suffered longer mechanical ventilation days (p = .015) and ICU stay days (p = .011). AKI stage 2–3 patients had higher risk of 1-year mortality (HR 16.98 (95% CI: 2.25–128.45)) compared with no-AKI and stage 1 patients.ConclusionsOur results suggested early post-operative AKI may be associated with higher baseline eGFR and TAC concentrations. AKI stage 1 may have no influence on survival rate, whereas AKI stage 2–3 may be associated with increased mortality at 1-year.     

Association of D-dimer and acute kidney injury associated with rhabdomyolysis in patients with exertional heatstroke: an over 10-year intensive care survey

Patients with rhabdomyolysis (RM) following exertional heatstroke (EHS) are often accompanied by dysfunction of coagulation and acute kidney injury (AKI). The purpose of this study was to investigate the relationship between D-dimer and AKI in patients with RM following EHS. A retrospective study was performed on patients with EHS admitted to the intensive care unit over 10-year. Data including baseline clinical information at admission, vital organ dysfunction, and 90-day mortality were collected. A total of 84 patients were finally included, of whom 41 (48.8%) had AKI. AKI patients had more severe organ injury and higher 90-day mortality (34.1 vs.0.0%, p < 0.001) than non-AKI patients. Multivariate logistic analysis showed that D-dimer (OR 1.3, 95% CI 1.1–1.7, p = 0.018) was an independent risk factor for AKI with RM following EHS. Curve fitting showed a curve relationship between D-dimer and AKI. Two-piecewise linear regression showed that D-dimer was associated with AKI in all populations (OR 1.3, 95% CI 1.2–1.5, p < 0.001) when D-dimer <10.0 mg/L, in RM group (OR 1.3, 95% CI 1.1–1.5, p < 0.001) when D-dimer >0.4 mg/L, in the non-RM group (OR 6.4, 95% CI 1.7–23.9, p = 0.005) when D-dimer <1.3 mg/L and D-dimer did not increase the incidence of AKI in the non-RM group when D-dimer >1.3 mg/L. AKI is a life-threatening complication of RM following EHS. D-dimer is associated with AKI in critically ill patients with EHS. The relationship between D-dimer and AKI depends on whether RM is present or not.     

Preoperative proteinuria may be a risk factor for postoperative acute kidney injury：a meta-analysis

ObjectiveTo investigate the relationship between preoperative proteinuria and postoperative acute kidney injury (AKI).MethodsWe performed a search on databases included PubMed, Embase, the Cochrane Library, and Web of Science, from December 2009 to September 2020. Data extracted from eligible studies were synthesized to calculate the odds ratio (OR) and 95% confidence interval (CI). A fixed or random effects model was applied to calculate the pooled OR based on heterogeneity through the included studies.ResultsThis meta-analysis of 11 observational studies included 203,987 participants, of whom 21,621 patients suffered from postoperative AKI and 182,366 patients did not suffer from postoperative AKI. The combined results demonstrated that preoperative proteinuria is an independent risk factor for postoperative AKI (adjusted OR = 1.65, 95%CI:1.44–1.89, p < 0.001). Subgroup analysis showed that both preoperative mild proteinuria (adjusted OR = 1.30, 95%CI:1.24–1.36, p < 0.001) and preoperative heavy proteinuria (adjusted OR = 1.93, 95%CI:1.65–2.27, p < 0.001) were independent risk factors for postoperative AKI. The heterogeneity was combined because its values were lower. Further subgroup analysis found that preoperative proteinuria measured using dipstick was an independent risk factor for postoperative AKI (adjusted OR = 1.48, 95%CI:1.37–1.60, p < 0.001). Finally, preoperative proteinuria was an independent risk factor for postoperative AKI in the non-cardiac surgery group (adjusted OR = 2.06, 95%CI:1.31–3.24, p = 0.002) and cardiac surgery group (adjusted OR = 1.69, 95%CI:1.39–2.06, p < 0.001)ConclusionPreoperative proteinuria is an independent risk factor for postoperative AKI and in instances when proteinuria is detected using dipsticks.     

Development and validation of a nomogram for predicting acute kidney injury after orthotopic liver transplantation

BackgroundWe aim to develop and validate a nomogram model for predicting severe acute kidney injury (AKI) after orthotopic liver transplantation (OLT).MethodsA total of 576 patients who received OLT in our center were enrolled. They were assigned to the development and validation cohort according to the time of inclusion. Univariable and multivariable logistic regression using the forward variable selection routine were applied to find risk factors for post-OLT severe AKI. Based on the results of multivariable analysis, a nomogram was developed and validated. Patients were followed up to assess the long-term mortality and development of chronic kidney disease (CKD).ResultsOverall, 35.9% of patients were diagnosed with severe AKI. Multivariable logistic regression analysis revealed that recipients’ BMI (OR 1.10, 95% CI 1.04–1.17, p = 0.012), hypertension (OR 2.32, 95% CI 1.22–4.45, p = 0.010), preoperative serum creatine (sCr) (OR 0.96, 95% CI 0.95–0.97, p < 0.001), and intraoperative fresh frozen plasm (FFP) transfusion (OR for each 1000 ml increase 1.34, 95% CI 1.03–1.75, p = 0.031) were independent risk factors for post-OLT severe AKI. They were all incorporated into the nomogram. The area under the ROC curve (AUC) was 0.73 (p < 0.05) and 0.81 (p < 0.05) in the development and validation cohort. The calibration curve demonstrated the predicted probabilities of severe AKI agreed with the observed probabilities (p > 0.05). Kaplan-Meier survival analysis showed that patients in the high-risk group stratified by the nomogram suffered significantly poorer long-term survival than the low-risk group (HR 1.92, p < 0.01). The cumulative risk of CKD was higher in the severe AKI group than no severe AKI group after competitive risk analysis (HR 1.48, p < 0.05).ConclusionsWith excellent predictive abilities, the nomogram may be a simple and reliable tool to identify patients at high risk for severe AKI and poor long-term prognosis after OLT.     

Monocyte-to-lymphocyte ratio: a potential novel predictor for acute kidney injury in the intensive care unit

Monocyte-to-lymphocyte ratio (MLR) and neutrophil-to-lymphocyte ratio (NLR) are considered as surrogate inflammatory indexes. Previous studies indicated that NLR was associated with the development of septic acute kidney injury (AKI). The objective of the present study was to explore the value of MLR and NLR in the occurrence of AKI in intensive care unit (ICU) patients. The clinical details of adult patients (n = 1500) who were admitted to the ICU from January 2016 to December 2019 were retrospectively examined. AKI was diagnosed according to the Kidney Disease: Improving Global Outcomes criteria. The development of AKI was the main outcome, and the secondary outcome was in-hospital mortality. Overall, 615 (41%) patients were diagnosed with AKI. Both MLR and NLR were positively correlated with AKI incidence (p < 0.001). Multivariate logistic regression analysis suggested that the risk value of MLR for the occurrence of AKI was nearly three-fold higher than NLR (OR = 3.904, 95% CI: 1.623‒9.391 vs. OR = 1.161, 95% CI: 1.135‒1.187, p < 0.001). The areas under the receiver operating characteristic curve (AUC) for MLR and NLR in the prediction of AKI incidence were 0.899 (95% CI: 0.881‒0.917) and 0.780 (95% CI: 0.755‒0.804) (all p < 0.001), with cutoff values of 0.693 and 12.4. However, the AUC of MLR and NLR in the prediction of in-hospital mortality was 0.583 (95% CI: 0.546‒0.620, p < 0.001) and 0.564 (95% CI: 0.528‒0.601, p = 0.001). MLR, an inexpensive and widely available parameter, is a reliable biomarker in predicting the occurrence of AKI in ICU patients.     

Intraoperative vasopressor use and early postoperative acute kidney injury in elderly patients undergoing elective noncardiac surgery

BackgroundIntraoperative hypotension is a risk factor for postoperative acute kidney injury (AKI). Elderly patients are susceptible due to reduced responses to acute hemodynamic changes.AimsDetermine the association between hypotension identified from anesthetic charts and postoperative AKI in elderly patients.MethodsRetrospective cohort study of elective noncardiac surgery patients ≥65 years, at an Australian tertiary hospital (December 2019–March 2021), with the primary outcome of AKI ≤48 h of surgery. Factors of interest were intraoperative hypotension determined from anesthetic charts (mean arterial pressure <60 mmHg, systolic blood pressure <90 mmHg, recorded 5-min) and intraoperative vasopressor use.ResultsIn 830 patients (mean age 75 years), systolic hypotension was more frequent than mean arterial hypotension (25.7% vs. 11.9%). Most hypotensive episodes were brief (7.2% of systolic and 4.2% of mean arterial hypotension lasted >10 min) but vasopressors were used in 84.7% of cases. The incidence of postoperative AKI was 13.9%. Systolic hypotension >20 min was associated with AKI (OR, 3.88; 95% CI: 1.38–10.9), which was not significant after adjusting for vasopressors, creatinine, American Society of Anesthesiologists class, and hemoglobin drop. The cumulative dose of any specific vasopressor >20 mg (or >10 mg epinephrine) was independently associated with AKI (adjusted OR, 2.47; 95% CI: 1.34–4.58). Every 5 mg increase in the total dose of all intraoperative vasopressors used during surgery was associated with 11% increased odds of AKI (95% CI: 3–19%).ConclusionsHigh vasopressor use was associated with postoperative AKI in elderly patients undergoing noncardiac surgery, independent of hypotension identified from anesthetic charts.     

Acute kidney injury after in-hospital cardiac arrest in a predominant internal medicine and cardiology patient population: incidence,risk factors,and impact on survival

IntroductionPrognosis of survivors from cardiac arrest is generally poor. Acute kidney injury (AKI) is a common finding in these patients. In general, AKI is well characterized as a marker of adverse outcome. In-hospital cardiac arrest (IHCA) represents a special subset of cardiac arrest scenarios with differential predisposing factors and courses after the event, compared to out-of-hospital resuscitations. Data about AKI in survivors after in-hospital cardiac arrest are scarce.MethodsIn this study, we retrospectively analyzed patients after IHCA for incidence and risk factors of AKI and its prognostic impact on mortality. For inclusion in the analysis, patients had to survive at least 48 h after IHCA.ResultsA total of 238 IHCA events with successful resuscitation and survival beyond 48 h after the initial event were recorded. Of those, 89.9% were patients of internal medicine, and 10.1% of patients from surgery, neurology or other departments. In 120/238 patients (50.4%), AKI was diagnosed. In 28 patients (23.3%), transient or permanent renal replacement therapy had to be initiated. Male gender, preexisting chronic kidney disease and a non-shockable first ECG rhythm during resuscitation were significantly associated with a higher incidence of AKI in IHCA-survivors. In-hospital mortality in survivors from IHCA without AKI was 29.7%, and 60.8% in patients after IHCA who developed AKI (p < 0.01 between groups).By multivariate analysis, AKI after IHCA persisted as an independent predictor of in-hospital mortality (HR 3.7 (95% CI 2.14–6.33, p ≤ 0.01)).ConclusionIn this cohort of survivors from IHCA, AKI is a frequent finding, with adverse impact on outcome. Therefore, therapeutic strategies to prevent AKI in post-IHCA patients are warranted.     

Urine N-terminal pro-B-type natriuretic peptide and plasma proenkephalin are promising biomarkers for early diagnosis of cardiorenal syndrome type 1 in acute decompensated heart failure: a prospective,double-center,observational study in real-world

BackgroundPatients with acute decompensated heart failure (ADHF) show cardiorenal syndrome type 1 (CRS-1) are more likely to have a poor outcome. However, the current criteria often lead to delayed CRS-1 diagnosis. Therefore, we evaluated the predictive value of plasma proenkephalin (pPENK) and urine NT-proBNP (uNT-proBNP) for early diagnosis of CRS-1 and vulnerable-phase prognosis in ADHF patients.MethodsThe plasma NT-proBNP (pNT-proBNP), pPENK, and uNT-proBNP were measured in 121 ADHF patients on admission. The plasma neutrophil gelatinase-associated lipocalin (pNGAL) was chosen as the reference. Logistic regression was used to determine the predictors of CRS-1. The area under the receiver operating curves (ROCs) was calculated to assess the early diagnostic value of pNGAL, pPENK, and uNT-proBNP/uCr for CRS-1. To evaluate the prognostic risk of factors for the 90-d outcomes of all ADHF patients, the Cox regression was performed and the cumulative risk curve was plotted.ResultsWe found that pPENK [OR 1.093 (95% CI 1.022–1.169), p = 0.010; AUROC = 0.899 (95% CI 0.831–0.946)] and uNT-proBNP/uCr ratio [OR 1.015 (95% CI 1.003–1.028), p = 0.012; AUROC = 0.934 (95% CI 0.874–0.971)] could independently predict the occurrence of CRS-1 in hospitalized patients with ADHF. The pPENK [HR 1.014 (95% CI 1.000–1.042), p = 0.044] and uNT-proBNP/uCr ration [HR 0.998 (95% CI 0.997–1.000), p = 0.045] were also independent predictors of the risk of HF readmission or all-cause death 90 d after discharge in ADHF patients.ConclusionsThe newly found pPENK and noninvasive test of uNT-proBNP/uCr ratio (pg/nmol) on admission may be two promising novel predictive biomarkers for early diagnosis of CRS-1 occurrence and vulnerable-phase outcomes in ADHF patients.     

The attributable mortality of sepsis for acute kidney injury: a propensity-matched analysis based on multicenter prospective cohort study

BackgroundBoth sepsis and AKI are diseases of major concern in intensive care unit (ICU). This study aimed to evaluate the excess mortality attributable to sepsis for acute kidney injury (AKI).MethodsA propensity score-matched analysis on a multicenter prospective cohort study in 18 Chinese ICUs was performed. Propensity score was sequentially conducted to match AKI patients with and without sepsis on day 1, day 2, and day 3–5. The primary outcome was hospital death of AKI patients.ResultsA total of 2008 AKI patients (40.9%) were eligible for the study. Of the 1010 AKI patients with sepsis, 619 (61.3%) were matched to 619 AKI patients in whom sepsis did not develop during the screening period of the study. The hospital mortality rate of matched AKI patients with sepsis was 205 of 619 (33.1%) compared with 150 of 619 (24.0%) for their matched AKI controls without sepsis (p = 0.001). The attributable mortality of total sepsis for AKI patients was 9.1% (95% CI: 4.8–13.3%). Of the matched patients with sepsis, 328 (53.0%) diagnosed septic shock. The attributable mortality of septic shock for AKI was 16.2% (95% CI: 11.3–20.8%, p < 0.001). Further, the attributable mortality of sepsis for AKI was 1.4% (95% CI: 4.1–5.9%, p = 0.825).ConclusionsThe attributable hospital mortality of total sepsis for AKI were 9.1%. Septic shock contributes to major excess mortality rate for AKI than sepsis.Registration for the multicenter prospective cohort studyregistration number ChiCTR-ECH-13003934     

Inhaled nitric oxide and acute kidney injury risk: a meta-analysis of randomized controlled trials

PurposeThere are conflicting results as to the effect of inhaled nitric oxide (iNO) therapy on the risk of acute kidney injury (AKI). The aim of this study was to perform a meta-analysis to assess the updated data.MethodsWe systematically searched Web of Science, the Cochrane Library, Wanfang, and PubMed for relevant randomized control trials between database inception and 9/07/2020. Relative risks (RRs) with 95% confidence intervals (CIs) predicting the risk of AKI were extracted to obtain summary estimates using fixed-effects models. The Trim and Fill method was used to evaluate the sensitivity of the results and adjust for publication bias in meta-analysis.Results15 randomized controlled studies from 14 articles involving 1853 patients were included in the study. Analyzing the eligible studies we found: (1) iNO therapy significantly increased the risk of AKI in acute respiratory distress syndrome patients (RR 1.55, 95% CI 1.15–2.10, p = 0.004; I² for heterogeneity 0%; P_het = 0.649). (2) The use of iNO was associated with reduced AKI risk in patients undergoing cardiac surgery (RR 0.80, 95% CI 0.64–0.99, p = 0.037; I² for heterogeneity 0%; P_het = 0.528). (3) For organ transplantation recipients, there was no effect of iNO administration on the risk of AKI (RR 0.50, 95% CI 0.16–1.56, p = 0.233; I² for heterogeneity 0%; P_het = 0.842). The Trim and Fill analysis showed that the overall effect of this meta-analysis was stable.ConclusionsThe effect of iNO on AKI risk might be disease-specific. Future RCTs with larger patient populations should aim to validate our findings.     

Hypophosphatemia is an independent risk factor for AKI among hospitalized patients with COVID-19 infection

BackgroundThis study sought to investigate incidence and risk factors for acute kidney injury (AKI) in hospitalized COVID-19.MethodsIn this retrospective study, we enrolled 823 COVID-19 patients with at least two evaluations of renal function during hospitalization from four hospitals in Wuhan, China between February 2020 and April 2020. Clinical and laboratory parameters at the time of admission and follow-up data were recorded. Systemic renal tubular dysfunction was evaluated via 24-h urine collections in a subgroup of 55 patients.ResultsIn total, 823 patients were enrolled (50.5% male) with a mean age of 60.9 ± 14.9 years. AKI occurred in 38 (40.9%) ICU cases but only 6 (0.8%) non-ICU cases. Using forward stepwise Cox regression analysis, we found eight independent risk factors for AKI including decreased platelet level, lower albumin level, lower phosphorus level, higher level of lactate dehydrogenase (LDH), procalcitonin, C-reactive protein (CRP), urea, and prothrombin time (PT) on admission. For every 0.1 mmol/L decreases in serum phosphorus level, patients had a 1.34-fold (95% CI 1.14–1.58) increased risk of AKI. Patients with hypophosphatemia were likely to be older and with lower lymphocyte count, lower serum albumin level, lower uric acid, higher LDH, and higher CRP. Furthermore, serum phosphorus level was positively correlated with phosphate tubular maximum per volume of filtrate (TmP/GFR) (Pearson r = 0.66, p < .001) in subgroup analysis, indicating renal phosphate loss via proximal renal tubular dysfunction.ConclusionThe AKI incidence was very low in non-ICU patients as compared to ICU patients. Hypophosphatemia is an independent risk factor for AKI in patients hospitalized for COVID-19 infection.     

Explainable machine learning model for predicting furosemide responsiveness in patients with oliguric acute kidney injury

BackgroundAlthough current guidelines didn’t support the routine use of furosemide in oliguric acute kidney injury (AKI) management, some patients may benefit from furosemide administration at an early stage. We aimed to develop an explainable machine learning (ML) model to differentiate between furosemide-responsive (FR) and furosemide-unresponsive (FU) oliguric AKI.MethodsFrom Medical Information Mart for Intensive Care-IV (MIMIC-IV) and eICU Collaborative Research Database (eICU-CRD), oliguric AKI patients with urine output (UO) < 0.5 ml/kg/h for the first 6 h after ICU admission and furosemide infusion ≥ 40 mg in the following 6 h were retrospectively selected. The MIMIC-IV cohort was used in training a XGBoost model to predict UO > 0.65 ml/kg/h during 6–24 h succeeding the initial 6 h for assessing oliguria, and it was validated in the eICU-CRD cohort. We compared the predictive performance of the XGBoost model with the traditional logistic regression and other ML models.Results6897 patients were included in the MIMIC-IV training cohort, with 2235 patients in the eICU-CRD validation cohort. The XGBoost model showed an AUC of 0.97 (95% CI: 0.96–0.98) for differentiating FR and FU oliguric AKI. It outperformed the logistic regression and other ML models in correctly predicting furosemide diuretic response, achieved 92.43% sensitivity (95% CI: 90.88–93.73%) and 95.12% specificity (95% CI: 93.51–96.3%).ConclusionA boosted ensemble algorithm can be used to accurately differentiate between patients who would and would not respond to furosemide in oliguric AKI. By making the model explainable, clinicians would be able to better understand the reasoning behind the prediction outcome and make individualized treatment.     

The effect of body mass index on the development of acute kidney injury and mortality in intensive care unit: is obesity paradox valid?

BackgroundThe conflicting results of studies on intensive care unit (ICU) mortality of obese patients and obese patients with acute kidney injury (AKI) reveal a paradox within a paradox. The aim of this study was to determine the effects of body mass index and obesity on AKI development and ICU mortality.MethodsThe 4,459 patients treated between January 2015 and December 2019 in the ICU at a Tertiary Care Center in Turkey were analyzed retrospectively.ResultsAKI developed more in obese patients with 69.8% (620). AKI development rates were similar in normal-weight (65.1%; 1172) and overweight patients (64.9%; 1149). The development of AKI in patients who presented with cerebrovascular diseases was higher in obese patients (81; 76.4%) than in normal-weight (158; 62.7%) and overweight (174; 60.8%) patients (p < 0.05). The risk of developing AKI was approximately 1.4 times (CI 95% = 1.177–1.662) higher in obese patients than in normal-weight patients. Dialysis was used more frequently in obese patients (24.3%, p < 0.001), who stayed longer in the ICU (p < 0.05). It was determined that the development of AKI in normal-weight and overweight patients increased mortality (p < 0.001) and that there was not a difference in mortality rates between obese patients with and without AKI.ConclusionThe risk of AKI development was higher in obese patients but not in those who were in serious conditions. Another paradox was that the development of AKI was associated with a higher mortality rate in normal-weight and overweight patients, but not in obese patients. Cerebrovascular diseases as a cause of admission pose additional risks for AKI.     

Predictors of mortality and cost among surgical patients requiring rapid response team activation

BackgroundPrior studies of rapid response team (RRT) implementation for surgical patients have demonstrated mixed results with respect to reductions in poor outcomes. The aim of this study was to identify predictors of in-hospital mortality and hospital costs among surgical inpatients requiring RRT activation.MethodsWe analyzed data prospectively collected from May 2012 to May 2016 at The Ottawa Hospital. We included patients who were at least 18 years of age, who were admitted to hospital, who received either preoperative or postoperative care, and and who required RRT activation. We created a multivariable logistic regression model to describe mortality predictors and a multivariable generalized linear model to describe cost predictors.ResultsWe included 1507 patients. The in-hospital mortality rate was 15.9%. The patient-related factors most strongly associated with mortality included an Elixhauser Comorbidity Index score of 20 or higher (odds ratio [OR] 3.60, 95% confidence interval [CI] 1.96–6.60) and care designations excluding admission to the intensive care unit and cardiopulmonary resuscitation (OR 3.52, 95% CI 2.25–5.52). The strongest surgical predictors included neurosurgical admission (OR 2.09, 95% CI 1.17–3.75), emergent surgery (OR 2.04, 95% CI 1.37–3.03) and occurrence of 2 or more operations (OR 1.73, 95% CI 1.21–2.46). Among RRT factors, occurrence of 2 or more RRT assessments (OR 2.01, 95% CI 1.44–2.80) conferred the highest mortality. Increased cost was strongly associated with admitting service, multiple surgeries, multiple RRT assessments and medical comorbidity.ConclusionRRT activation among surgical inpatients identifies a population at high risk of death. We identified several predictors of mortality and cost, which represent opportunities for future quality improvement and patient safety initiatives.